1. Technical Field
This invention relates to orthotic and prosthetics that have sensor devices used to continuously monitor the amount of pressure on soft tissue confined therein. Orthosis such as therapeutic ankle and foot brace support the patient""s foot for isolated pressure relief against portions thereof. Optimal outcome for such processes are jeopardized by improper refitting of the orthotics by the patient or unskilled caregiver.
2. Description of Prior Art
Prior art devices of this type have generally been directed to pressure sensing devices that measure the effective pressure on the patient""s foot with the supporting surfaces. Typically, such pressure sensing devices are integrated within the footwear such as shoes as seen in U.S. Pat. Nos. 4,647,918, 5,566,479, 5,642,096 and 5,678,448.
In U.S. Pat. No. 4,647,918 a multiple event pressure notification system is disclosed wherein multiple pressure monitoring points are arranged within the footwear and interconnected to a microprocessor programmed to detect varying pressure amounts and calculate same to time and locale. An alarm sounds when pressure exceeds a pre-programmed threshold at any one of the given pressure indicating points.
U.S. Pat. No. 5,566,479 discloses a shoe for diabetics or others having four sensor resistors that activate an alarm circuit when a pre-selected threshold pressure amounts are reached.
U.S. Pat. No. 5,642,096 uses a series of pizorisistois sensors arranged in arrayed pairs within the inner sole of the footwear in pressure increase and decrease arrays. The system measures both pressure and temperature through which the patient""s foot is exposed.
U.S. Pat. No. 5,678,448 defines a self-contained system to measure forces that are applied to the foot within the shoe by a matrix of four sensors covering the inner sole of the shoe.
Additional prior art is directed to pressure sensing systems to measure increasing pressure between the injured portion of a patient""s body and confinement, see, for example, U.S. Pat. No. 4,858,620 having a plurality of pressure sensors within an orthopedic restraining member that indicates once a critical pressure value is reached an alarm activation.
U.S. Pat. No. 5,790,256 is directed to a foot analyzer that uses both pressure sensing and optical sensors to analyze a patient""s foot placed within the sensing enclosure.
Finally, U.S. Pat. No. 5,838,214 refers to an interface pressure measurement device that interfaces between a patient""s foot and surrounding support surfaces. The device has two sensor sheets of thin flexible plastic material arranged so that when the sheets touch an electrical contact is presented forming a sensing switch.
A therapeutic ankle and foot apparatus having a contact sensor indicator whereby any physical pressure on the isolated portion of the patient""s foot will be detected and indicated by an auditory and visual activation alarm circuit. The contact sensor can be one of a variety of pressure or proximal activation switching elements positioned between the patient""s foot and the therapeutic ankle and foot apparatus.